Only about 20 per cent of illegal drugs imported into New Zealand is detected by Customs, says a report by the National Drug Intelligence Bureau.
The confidential report, released to 3 News, showed that for every drug haul made by Customs, five crossed the border.
Customs' interceptions of Contac NT,a Chinese cold medicine used to make methamphetamine, have risen by 1200 per cent in the past five years. But about 10 million tablets a year, or 2 per cent of China's total Contac NT production, were sent to New Zealand, enough to produce 630kg of methamphetamine.
